Who is this promising Canadian playwright?

When several shows open on the same night — a frequent occurrence in Chicago — we critics have to see some productions a little later. So that was how I came to roll up at the Signal Ensemble Theatre on Thursday of last week. It was a last-minute change of plan; I gave the theater almost no notice and received an abject lesson in how much some small Chicago theater companies without seasonal subscribers risk when they produce an unknown new play.

In the audience were the director, Ronan Marra, a couple of Saints (the volunteer usher corps), a guy by himself and maybe two couples. And me. Yet we shared one of the more gripping shows of the season so far: "East of Berlin" by a remarkable young Canadian playwright named Hannah Moscovitch.

Set in the 1950s and '60s, it's the powerful story of the son of a Nazi war criminal — a doctor at a concentration camp — who begins an inestimably complex relationship with the American daughter of one of the camp's victims. As performed by Billy Fenderson, Melanie Keller and Tom McGrath, this is one of those rare new plays where you buy into everything you are seeing, and fear for the needy characters at every turn. It is profoundly affecting. Or, to put it another way, the play blew me away. I had never even heard of Moscovitch.

So I emailed J. Kelly Nestruck, the theater critic at The Globe and Mail in Toronto and an authority on new Canadian plays. He wrote back straight away: "Yes. She's our great Canadian hope at the moment."

There was some irony there: Canadians involved in the theater (and journalism) are a self-deprecating lot, given the usual personalities attracted by such professions. But if that's the case, things are looking good for Canada.

Nestruck appended a profile he had written of Moscovitch, tracing her rise through the independent Toronto theater festival, SummerWorks, and noting the way her career exploded when "East of Berlin" premiered at Toronto's Tarragon Theatre near the end of 2007. He called the Ottawa-born Moscovitch "Canada's hottest young playwright." She is 33.

I wondered if the skilled actress Keller had something to do with Signal Ensemble snagging this play. I had run into Keller, a longtime Signal Ensemble Theatre member, a couple of years ago at the Stratford Shakespeare Festival. She had been sponsored by the Chicago friends of the prestigious theater festival — a group of Chicago-based supporters who have a lot of clout in Stratford, the summer destination of thousands of theater-loving Chicagoans. I asked Marra, the director.

Yes and no, he said. His literary manager, Bries Vannon, had actually found the script. But at the same time, Keller had brought in Moscovitch's "The Russian Play" — a short piece that Signal Ensemble is staging directly after the one-act "East of Berlin." She had indeed met Moscovitch in Stratford. Synchronicity, Marra thought. He put both scripts together on the same bill, to remarkable effect.

Last weekend, Moscovitch flew into town to watch her show. I finally caught up with her by phone, just as she was getting back to Toronto.

Aside from a very small production in Los Angeles (which she did not see), this was the first U.S. production of one of her scripts, she said. Mercifully, she had not had to sit in rows of empty seats. In fact, the theater had been oversold on that Saturday night. Moscovitch, who was making her first foray to the Chicago theater, couldn't stop talking about how Marra had staged her play, storefront-style, without any scenery. Those hit Canadian productions had used all kinds of stuff. This, she said, was something quite different.

"I always thought it could be done that way," she said. "But I had to come to Chicago to see how."

Word about her is most certainly out. This week, the Stratford festival is announcing that it has given Moscovitch a commission. And those savvy new-play folks at the Manhattan Theatre Club (ever on top of their game) have done the same. Moscovitch's work has yet to be seen in New York. But in Chicago right now, you have an excellent opportunity to experience not just a Canadian hope, but a great Canadian bet for a provocative night out.

"East of Berlin" is playing through Nov. 13 at Signal Ensemble Theatre, 1802 W. Berenice Ave.; $20 at 773-698-7389 or signalensemble.com.

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